TT virus infection in end-stage renal disease (ESRD)

TT virus is a novel hepatitis-associated DNA virus that has been provisionally designated as transfusion-transmitted virus (TTV). Infection by TTV has been frequently demonstrated in humans. Few reports, however, have been published on the epidemiology of TTV infection in patients with ESRD. The prevalence of TTV in patients undergoing maintenance dialysis varies widely and various demographic, virologic or clinical features can explain these differences; in some series, the prevalence of TTV in HD was significantly higher than in control groups. Blood transfusion requirement and nosocomial transmission of TTV within dialysis units seem to be important in the diffusion of TTV in the HD setting; however, other routes of TTV acquisition may play a role. The clinical significance related to the presence of TTV in HD population remains unclear; it is possible that TTV may aggravate liver disease caused by hepatitis C virus (HCV) infection. The natural history of TTV in dialysis is an area of avide research, since TTV has a propensity for establishing long-term infection in HD patients. The possibility that TTV causes pathological changes outside the liver cannot be ruled out. Further studies are in progress to understand the natural history and the epidemiology of TTV infection in patients with ESRD.